James Wadleigh had more than three decades to learn the pitfalls of contemporary drug dealing. He was convicted for possession in 1981, for distribution in 1983, and for numerous similar offenses in the years that followed. In 2012, he was robbed at gunpoint and fled with a suitcase full of drugs before being arrested.

By last year, authorities said yesterday, the 51-year-old from Pembroke had honed his craft. He was still dealing, they said, but in an indirect, managerial role: Profits were placed in safe deposit boxes, drugs – heroin, cocaine and prescription pills – were stored in a neighbor’s apartment, and hand-to-hand transactions were carried out by a local 18-year-old named Brett Carter.

His enterprise, as Pembroke police Chief Dwayne Gilman described it yesterday, included at least seven people from Pembroke and Allenstown. They were all arrested, in addition to Wadleigh, late Thursday on drug-related charges.

The sweep was the result of a nearly yearlong investigation, including four to six months of undercover work managed by the state Drug Task Force, Gilman said. He said authorities raided residences in both towns, including Wadleigh’s apartment at 197 Main St., and seized “considerable” amounts of drugs and more than $10,000 in cash.

“This is a huge hit for Pembroke,” Gilman said.

Wadleigh is charged with eight felony counts of conspiracy to sell controlled drugs. A judge in Concord’s district court ordered him held on $400,000 cash bail – by far the highest of the eight.

Ashlie Hooper, an assistant county prosecutor, said Wadleigh was the linchpin in the operation. He drove routinely to Massachusetts to pick up drugs in bulk, Hooper said, then brought them back to Pembroke and stored them with the neighbor, Angie Horn, 39. Hooper said Horn sometime packaged heroin in her kitchen, and that her young child lived with her in the apartment.

Horn, who has a criminal conviction record dating back to 2002, is charged with three felonies of selling cocaine between March 6 and 14. She is being held on $30,000 cash bail.

Wadleigh was convicted in January of the 2012 drug possession charges. He received probation and a suspended sentence in exchange for information about another dealer. He also testified in Merrimack County Superior Court in January in the case involving his attacker, Richard Grandmont.

Carter, one of two 18-year-olds arrested, is charged with nine felonies of selling cocaine between Feb. 27 and March 19. During a video arraignment, Hooper said he organized the time and location of deals and carried them out, often getting a ride from Wadleigh. Hooper said after the hearing that she was unsure of how the two initially met.

Carter turned 18 in October, according to his criminal complaints, but he appeared younger yesterday on screen, his cheeks full and flush, an orange jail shirt draped over his slender frame. He did not have a criminal record, Hooper said, but his grandmother, who was in court and later declined to give her name, hinted at past struggles.

“I thought he was working in drywall,” she told the judge. “He looks better than he looked in a long time, so I really thought he was doing well.”

She said she had tried to get him help. “I went up to (Hooksett’s district) court and practically begged that judge to put him in juvenile placement,” she said. “And he didn’t. And so . . . now we’re here.”

Carter is being held on $45,000 cash bail. Another suspect, Julie Brasseau, who is accused of selling prescription pills on four occasions last year, is being held on $20,000 cash bail. All four are scheduled for probable cause hearings, in which a judge decides whether there is enough evidence for a case to move forward, on April 7 in Hooksett.

The remaining four suspects – Corie Clemmer, 36, of Allenstown; Kristi Devlin, 35, of Allenstown; Roland M. Thibeault, 18, of Pembroke; and Roland Thibeault, 47, of Pembroke – are accused of playing smaller roles and have each been released on personal recognizance bail. The Thibeaults are father and son, Gilman said.

Arrest affidavits detailing the investigation have been sealed. In a statement yesterday, Pembroke officials said the investigation was a collaboration between their department, the state task force, the state police, Concord’s drug task force and the Allenstown police.

More arrests are expected, the statement indicated.

(Jeremy Blackman can be reached at 369-3319, jblackman@cmonitor.com or on Twitter @JBlackmanCM.)